Creates RootWindowControllerCommon

ash/root_window_controller.h

Index: ash/root_window_controller.h
diff --git a/ash/root_window_controller.h b/ash/root_window_controller.h
index 1dcf688f7eaefc07177170d23bc1b861c5052682..04ebd2ffa9f465e47f48015fa075b082a13a2910 100644
--- a/ash/root_window_controller.h
+++ b/ash/root_window_controller.h
@@ -56,6 +56,7 @@ class AnimatingDesktopController;
 class DesktopBackgroundWidgetController;
 class DockedWindowLayoutManager;
 class PanelLayoutManager;
+class RootWindowControllerCommon;
 class RootWindowLayoutManager;
 class ShelfLayoutManager;
 class ShelfWidget;
@@ -251,10 +252,6 @@ class ASH_EXPORT RootWindowController : public ShellObserver {
   // |is_first_run_after_boot| determines the background's initial color.
   void CreateSystemBackground(bool is_first_run_after_boot);
 
-  // Creates each of the special window containers that holds windows of various
-  // types in the shell UI.
-  void CreateContainersInRootWindow(wm::WmWindow* root_window);
-
   // Enables projection touch HUD.
   void EnableTouchHudProjection();
 
@@ -269,6 +266,9 @@ class ASH_EXPORT RootWindowController : public ShellObserver {
   void OnTouchHudProjectionToggled(bool enabled) override;
 
   std::unique_ptr<AshWindowTreeHost> ash_host_;
+
+  std::unique_ptr<RootWindowControllerCommon> root_window_controller_common_;
+
   RootWindowLayoutManager* root_window_layout_;
 
   std::unique_ptr<StackingController> stacking_controller_;